A man blocked from working at the State Department is at the center of Hillary Clinton's latest controversy

Former Secretary of State Hillary Clinton. Scott Olson/Getty Images WASHINGTON (AP) — Longtime Clinton confidant Sidney Blumenthal had been blocked from working for Hillary Rodham Clinton at the State Department by wary White House officials. But that didn't cut his direct line to Clinton on one of the most sensitive matters of her tenure at the agency.

During Clinton's years as secretary of state, Blumenthal offered a flood of intelligence and advice to his former boss, sending near-monthly missives about the growing unrest in Libya to the personal email account she continued to use as a government employee.

The correspondence, which covered everything from warring Middle Eastern factions to political strategy, was absorbed by Clinton, who often forwarded the messages to aides with the instruction "pls print."

Clinton's earlier efforts to hire Blumenthal, who has spent nearly two decades working for the Clinton family, as a State Department employee had been rejected by Obama administration officials who said they feared his role spreading harsh attacks against Obama in the 2008 presidential primaries would cause discomfort among members of their new White House team.

But his continued role was revealed in nearly 350 pages of emails, published Thursday by The New York Times, about the 2012 attacks on the U.S. diplomatic post in Benghazi, Libya, that killed four Americans, including U.S. Ambassador Christopher Stevens.

Clinton, the front-runner for the Democratic nomination for president, gave the State Department 55,000 pages of emails last year that she said pertained to her work as secretary sent from the personal address she used while at the agency. The messages about the events in Libya were given for review to a special House panel investigating the attacks and are expected to be released by the State Department in the coming days after months of delay.

The panel, which was initially formed to investigate Stevens' death, has become a vehicle to broadly question Clinton's tenure at the State Department, revealing potential ammunition for Republican attacks on the 2016 campaign trail. This week, the panel subpoenaed Blumenthal to testify on Capitol Hill.

Blumenthal, through his lawyer, told The Washington Post on Thursday that he will cooperate with the congressional inquiry.

There is nothing in the emails to suggest that Clinton was actively soliciting Blumenthal's advice or alleged intelligence information, although the documents contain few replies she may have sent to him. Her responses are polite, in one case thanking him for "useful" information.

The sources of Blumenthal's information are often unclear. At the time, he was working for the Clinton family foundation and advising a group of entrepreneurs trying to win business from the Libyan transitional government.

Some of Blumenthal's analysis, often forwarded by aides without revealing their author, was questioned by State Department officials. Gene Cretz, Stevens' predecessor as U.S. ambassador to Libya, described one note as "odd," and said the author appeared to have confused two individuals with similar names.

Passing on an April Blumenthal note, Clinton wrote deputy chief of staff Jake Sullivan: "This one strains credulity. What do you think?"

The report claimed French and British intelligence services were activating longstanding contacts with tribal leaders in Libya, encouraging them to establish a breakaway, semi-autonomous area.

Much of the contents deal with the internal infighting that still plagues Libya, as weak political leaders failed to disarm powerful revolutionary militias and different armed commanders battled among themselves for the nation's spoils.

The evening after the Benghazi attack, Blumenthal forwarded to Clinton an analysis of the situation from former CIA official Tyler Drumheller which purported to contain information from "sources with direct access to the Libyan National Transitional Council as well as the highest levels of European governments as well as Western intelligence and security services."

The memo said a top Libyan official, Mohamed Yousef el-Magariaf, had told close associates that the Benghazi attack was carried out by the militant group Ansar al-Sharia and that Libyan security officials believed the group "took advantage of cover provided by" demonstrations against the internet video seen as insulting to the Prophet Mohammed to conduct it.

The memo, citing an unidentified source passing on information from unnamed Libyan security officials, said that 21 members of Ansar al-Sharia had joined with about 2,000 demonstrators outside the Benghazi facility. Citing the same source, the memo said that some Libyan officials believed the protest was organized solely as cover for the attack.

The unidentified source cited by Drumheller said some Libyan security officials had told el-Magariaf that the group had been planning the attack for about a month.

Clinton forwarded Blumenthal's email to Sullivan, her deputy chief of staff, with the instruction, "We should get around this asap," to which Sullivan replied, "Will do." Clinton also forwarded the email to another person, whose identity is redacted, with the instruction "pls print."

Other emails to Clinton from Blumenthal in the aftermath of the attack offer additional material from similar unnamed sources describing Egyptian and Libyan governments' concerns about the situation and growing sectarian violence. They also contained rumor and speculation about various internal Libyan government deliberations.

In January 2012, eight months before the Sept. 11 attack on the U.S. outpost, he tells Clinton how 2,000 disgruntled veterans, supported by students, attacked the Benghazi headquarters of Libya's struggling, post-Gadhafi government. They threw Molotov cocktails and beat government employees, he claimed, and destroyed equipment and files.

From time to time, Blumenthal commented on the administration's political strategy. In October 2012, a month before President Barack Obama was re-elected, he also passed along a news article predicting that the Republicans might try to use Benghazi as a campaign tool in the run-up to the 2012 presidential election. Five hours later, Clinton replied to Blumenthal, saying: "Thanks. I'm pushing to the WH."

At the same time, according to the time stamp on the email, she also forwarded the article to Sullivan with the notation, "Be sure Ben knows they need to be ready for this line of attack." The identity of "Ben" is not disclosed but may be a reference to Obama's deputy national security adviser Ben Rhodes. Sullivan replied, "Will do," according to the emails.

In an Oct. 7, conversation chain, Blumenthal invited the secretary of state to dinner at his home at an unspecified date after the November election. "Bill can come, too, if he's in town. Whatever works." Clinton's reply to the invitation, if there was one, was not included.